Manual ventilation quality is improved with a real-time visual feedback system during simulated resuscitation.

Introduction: Manual ventilations during cardiac arrest are frequently performed outside of recommended guidelines. Real-time feedback has been shown to improve chest compression quality, but the use of feedback to guide ventilation volume and rate has not been studied. The purpose of this study was to determine whether the use of a real-time visual feedback system for ventilation volume and rate improves manual ventilation quality during simulated cardiac arrest.

Nocturnal bilevel positive airway pressure for the treatment of asthma.

Nocturnal worsening of asthma may be due to reduced lung volumes and fewer sigh breaths, which have been shown to increase airway resistance and bronchoreactivity. We hypothesized that mimicking deep inspiration using nocturnal mechanical support would improve symptoms in patients with asthma. Subjects with asthma underwent usual care and bilevel positive airway pressure (PAP) therapy for 4 weeks, separated by 4 weeks, and methacholine challenge (PC) and subjective assessments.

Non-invasive respiratory volume monitoring to detect apnea in post-operative patients: case series.

Obstructive sleep apnea (OSA) is a potential independent risk factor for postoperative complications, adverse surgical outcomes, and longer hospital stays. Obese patients with OSA have increased post-operative complications. An estimated 25-30% of pre-operative patients are at a high risk for OSA.

A pilot study investigating the effects of continuous positive airway pressure treatment and weight-loss surgery on autonomic activity in obese obstructive sleep apnea patients.

Background: We have previously demonstrated that severity of obstructive sleep apnea (OSA) as measured by the apnea-hypopnea index (AHI) is a significant independent predictor of readily-computed time-domain metrics of short-term heart rate variability (HRV).

Methods: We aimed to assess time-domain HRV measured over 5-min while awake in a trial of obese subjects undergoing one of two OSA therapies: weight-loss surgery (n=12, 2 males, median and interquartile range (IQR) for BMI 43.7 [42.

Acetazolamide attenuates the ventilatory response to arousal in patients with obstructive sleep apnea.

Study Objectives: The magnitude of the post-apnea/hypopnea ventilatory overshoot following arousal may perpetuate subsequent respiratory events in obstructive sleep apnea (OSA) patients, potentially contributing to the disorder's severity. As acetazolamide can reduce apnea severity in some patients, we examined the effect of acetazolamide on the ventilatory response to spontaneous arousals in CPAP-treated OSA patients.

Design: We assessed the ventilatory response to arousal in OSA patients on therapeutic CPAP before and after administration of acetazolamide for 7 days.

Sitting and supine esophageal pressures in overweight and obese subjects.

Esophageal pressure (P(Es)) can be used to approximate pleural pressure (P(pl)) and might be clinically useful, particularly in the obese e.g., to guide mechanical ventilator settings in critical illness.

Measuring upper and lower airway resistance during sleep with the forced oscillation technique.

The forced oscillation technique (FOT) is a non-invasive technique to monitor airway obstruction in those with asthma. The aim of this study was to design and validate a system to use FOT during sleep, both with and without bi-level positive airway pressure (BPAP), and to separate upper airway resistance from lower. 8 Hz pressure oscillations were supplied, over which the subject breathed, pressure and flow measurements were then used to calculate impedance.

Neurogenic changes in the upper airway of patients with obstructive sleep apnea.

Rationale: Controversy persists regarding the presence and importance of hypoglossal nerve dysfunction in obstructive sleep apnea (OSA).

Objectives: We assessed quantitative parameters related to motor unit potential (MUP) morphology derived from electromyographic (EMG) signals in patients with OSA versus control subjects and hypothesized that signs of neurogenic remodeling would be present in the patients with OSA.

Methods: Participants underwent diagnostic sleep studies to obtain apnea-hypopnea indices.

A possible method to predict response to non-pharmacological insomnia therapy.

Study Objectives: To determine if electrocardiographic parameters are predictive of response to non-pharmacological insomnia therapy.

Design: Secondary analysis of heart rate parameters from a double blind, randomized, sham-controlled trial at multiple study sites.

Setting: Six sites in the United States were used for the data collection.

Pathophysiology & genetics of obstructive sleep apnoea.

Obstructive sleep apnoea (OSA) is a highly prevalent condition with proven neurocognitive and cardiovascular consequences. OSA patients experience repetitive narrowing or collapse of the pharyngeal airway during sleep. Multiple factors likely underlie the pathophysiology of this condition with considerable inter-individual variation.

Probing airway conditions governing ventilation defects in asthma via hyperpolarized MRI image functional modeling.

Image functional modeling (IFM) has been introduced as a method to simultaneously synthesize imaging and mechanical data with computational models to determine the degree and location of airway constriction in asthma. Using lung imaging provided by hyperpolarized (3)He MRI, we advanced our IFM method to require matching not only to ventilation defect location but to specific ventilation throughout the lung. Imaging and mechanical data were acquired for four healthy and four asthmatic subjects pre- and postbronchial challenge.